Stability of the Pigment from Black Beauty Potato

In order to investigate physiochemical properties and stability of the pigment from Black Beauty potato,the change in maximum absorption wavelength of this pigment under different conditions was determined through a spectrophotometer.Results indicated that this pigment was a water-soluble anthocyanin.An obvious effect of pH on stability of this pigment was observed and this pigment exhibited better stability in acidic environments.In addition,Al3+ revealed an color enhancement effect on this pigment,while Na+,K+,Ca2+,Mg2+,Zn2+ exhibited little effect.In contrast,Cu2+ and Fe3+ contributed obvious adverse effects on stability.This pigment also exhibited strong resistance to radiation,but poor resistance to oxidation,light and heat.Although no obvious effects of sucrose at low concentration,VC and β-CD on stability of this pigment were observed,an enhanced effect of citric acid on pigment was observed.These investigations demonstrated exploitation and utilization values of this pigment in the industry of food additives.